MatthewVD writes: "In 2006, researcher Mark Changizi came up with a novel theory for why humans evolved with color vision: to detect social cues and emotions in others. He built glasses called 02Amps to enhance perception of blood pooling. Some hospitals have tried using the glasses to see bruising that's not visible unaided, or help nurses find veins. But it turns out now that the glasses might be able to fix some forms of colorblindness, too."